* {
  margin: 0;
  padding: 0;
}
body {
  max-width: 1920px;
  min-width: 1200px;
  height: auto;
}
.banner {
  position: relative;
  width: 720px;
  height: 455px;
  background-color: purple;
  margin: 200px auto;
  overflow: hidden;
}
.btn_left,
.btn_right {
  /* display: none; */
  position: absolute;
  top: 50%;
  margin-top: -20px;
  width: 24px;
  height: 40px;
  background: rgba(0, 0, 0, 0.3);
  text-align: center;
  line-height: 40px;
  color: #fff;
  font-family: 'icomoon';
  font-size: 18px;
  z-index: 2;
  cursor: pointer;
}
.btn_right {
  right: 0;
}
.content {
  position: absolute;
  top: 0;
  left: 0;
  display: flex;
  width: 720px;
  height: 100%;
}
.content li {
  width: 100% !important;
  height: 100%;
  list-style: none;
  flex-shrink: 0;
}
.content .li1 {
  background: url(../img/focus.jpg) center / cover no-repeat;
}
.content .li2 {
  background: url(../img/focus1.jpg) center / cover no-repeat;
}
.content .li3 {
  background: url(../img/focus2.jpg) center / cover no-repeat;
}
.content .li4 {
  background: url(../img/focus3.jpg) center / cover no-repeat;
}
.circle {
  position: absolute;
  display: flex;
  bottom: 10px;
  left: 10px;
  width: auto;
  height: auto;
  z-index: 2;
}
.circle li {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 3px solid #fff;
  list-style: none;
  margin: 0 5px 0 0;
  cursor: pointer;
}
.current {
  background-color: #fff;
}
